Proteomics, Metabolomics, And Protein Interactomics In The Characterization Of The Molecular Features Of Major Depressive Disorder.

Omics technologies emerged as complementary strategies to genomics in the attempt to understand human illnesses. In general, proteomics technologies emerged earlier than those of metabolomics for major depressive disorder (MDD) research, but both are driven by the identification of proteins and/or metabolites that can delineate a comprehensive characterization of MDD's molecular mechanisms, as well as lead to the identification of biomarker candidates of all types-prognosis, diagnosis, treatment, and patient stratification. Also, one can explore protein and metabolite interactomes in order to pinpoint additional molecules associated with the disease that had not been picked up initially. Here, results and methodological aspects of MDD research using proteomics, metabolomics, and protein interactomics are reviewed, focusing on human samples.1663-7

Molecular studies in schizophrenia

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Shotgun Mass Spectrometry Workflow Combining IEF and LC-MALDI-TOF/TOF

We present a high throughput shotgun mass spectrometry workflow using a bidimensional peptide fractionation procedure consisting of isoelectric focusing and RP-HPLC prior to mass spectrometric analysis, with the aim of optimizing peptide separation and protein identification. As part of the workflow we used the ‘Isotope-Coded Protein Labeling’ (ICPL) method for accurate relative quantitation of protein expression. Such workflow was successfully applied to a comparative proteome analysis of schizophrenia versus healthy control brain tissues and can be an alternative to proteome researches

Biochemical Pathways Triggered by Antipsychotics in Human Oligodendrocytes: Potential of Discovering New Treatment Targets

Schizophrenia is a psychiatric disorder that affects more than 21 million people worldwide. It is an incurable disorder and the primary means of managing symptoms is through administration of pharmacological treatments, which consist heavily of antipsychotics. First-generation antipsychotics have the properties of D2 receptor antagonists. Second-generation antipsychotics are antagonists of both D2 and 5HT2 receptors. Recently, there has been increasing interest in the effects of antipsychotics beyond their neuronal targets and oligodendrocytes are one of the main candidates. Thus, our aim was to evaluate the molecular effects of typical and atypical drugs across the proteome of the human oligodendrocyte cell line, MO3.13. For this, we performed a mass spectrometry-based, bottom-up shotgun proteomic analysis to identify differences triggered by typical (chlorpromazine and haloperidol) and atypical (quetiapine and risperidone) antipsychotics. Proteins which showed changes in their expression levels were analyzed in silico using Ingenuity® Pathway Analysis, which implicated dysregulation of canonical pathways for each treatment. Our results shed light on the biochemical pathways involved in the mechanisms of action of these drugs, which may guide the identification of novel biomarkers and the development of new and improved treatments

Determination of gene expression and proteome of brain tissue from schizophrenic patients

Orientador: Emmanuel Dias-NetoTese (doutorado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: A esquizofrenia é um distúrbio mental debilitante que afeta aproximadamente 1% da população mundial, caracterizado por sintomas produtivos como delírios e alucinações e sintomas negativos como apatia e decréscimo das emoções. Nesta tese, realizamos estudos do transcriptoma e do proteoma em tecido cerebral de pacientes com esquizofrenia, buscando identificar genes e proteínas envolvidas com esta doença. Em nossas análises transcricionais, utilizamos a técnica de Serial Analysis of Gene xpression (SAGE), uma abordagem ainda inédita em esquizofrenia. Os dados permitiram a análise de mais de 20 mil transcritos, e apontaram para o possível envolvimento de genes associados a processos como mielinização, função sináptica, metabolismo energético e homeostase de cálcio, incluindo genes anteriormente envolvidos com esquizofrenia, e também uma boa parcela de genes até então não associados com a doença. Uma pequena fração destes novos marcadores foi avaliada por Real-Time PCR permitindo a confirmação de alguns achados de SAGE. ossas análises de proteoma foram feitas com as técnicas de eletroforese de duas dimensões, seguida por espectrometria de massas e pela técnica de shotgun proteomics, também inédita em esquizofrenia. Estas análises foram realizadas com amostras de diferentes regiões cerebrais, incluindo córtex pré-frontal e lobo temporal anterior, e apontaram para alterações quantitativas em proteínas relacionadas com a homeostase de cálcio, citoesqueleto, metabolismo energético e de oligodendrócitos. De modo geral, observamos uma boa consistência entre os resultados obtidos quando estudamos diferentes classes de marcadores potenciais (genes e proteínas). Por muitas vezes os genes alterados não corresponderam a alterações quantitativas nas mesmas proteínas, no entanto, na maior parte dos casos, observamos alterações consistentes nas mesmas vias. Observamos a regulação diferencial do metabolismo de oligodendrócitos, energético, sináptico e revelamos a provável alteração da homeostase de cálcio em cérebros de pacientes com esquizofrenia, além de identificarmos genes e proteínas diferencialmente expressas nunca relacionadas à doença. Nossos dados reforçam achados prévios, apontam potenciais biomarcadores e podem fornecer novas pistas na compreensão da esquizofreniaAbstract: Schizophrenia is a mental debilitating disorder that affects 1% of the world population. It is characterized by positives symptoms such as delirium and hallucinations and negative symptoms such as apathy and emotion decrease. Here, we have studied the ranscriptome and proteome of brain samples of patients with schizophrenia, in an attempt to identify genes and proteins markers of the disease. Our transcriptome analyses of pre-frontal cortex were performed with Serial Analysis of Gene Expression (SAGE), here used for the first time in the study of schizophrenia. The data obtained allowed the analysis of approximately 20,000 transcripts, which suggested the importance of myelinization, synaptic function, energy metabolism and calcium homeostasis, in the genesis of schizophrenia. A series of genes previously implicated in the disease were identified, together with new potential markers which were revealed here for the first time. A small fraction of these was validated using realtime PCR, which confirmed some of the SAGE findings. Two-dimensional gel electrophoresis, mass spectrometry and shotgun proteomics were the approaches used here for large-scale protein analysis in schizophrenia. These approaches were used in brain samples derived from distinct areas such as pre-frontal cortex and anterior temporal lobe, and indicated quanitative alterations of proteins involved with calcium homeostasis, energy and oligodendrocyte metabolism and cytoskeleton. In general, a good correlation was observed when the different approaches (transcriptome and proteome) were used. In may cases, the alterations of some genes was not reflected by a correspondent alteration of the encoded protein. However, in most cases, reproducible alterations were found in the same pathways. Beside the identification of new schizophrenia-related genes and proteins, we also confirmed the the differential regulation of oligodendrocyte, synaptic and energetic metabolism, in this disease.Our data reinforce previous findings, and suggest new potential biomarkers that may contribute to the understanding of schizophreniaDoutoradoBioquimicaDoutor em Biologia Funcional e Molecula